Within 3GPP, work has recently started on a new Work Item called Multi Access PDN connectivity and IP flow mobility, MAPIM. The intention is to introduce support for simultaneous access from a terminal to multiple heterogeneous access networks (technologies) such as UMTS/GPRS, LTE, WLAN, WiMax, DOCSYS and fixed broadband access. In a possible scenario, a terminal would use both e.g. WCDMA access and WLAN access to access the same destination Packet Data Network, PDN, using one and the same IP-session. The system would then support operator defined policies for service-based routing of the UE IP-flows via different access systems.